JP3826710B2 - Seal molding equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sealing molding apparatus that seals and molds electronic components, semiconductors, and the like with a thermosetting resin or the like.
[0002]
[Prior art]
A conventional sealing molding apparatus will be described with reference to the drawings. 10 is a perspective view of a main part of a conventional sealing molding apparatus, FIGS. 11A and 11B are sectional views showing the operation of the plunger before and after resin injection during the sealing molding, and FIG. FIG. 13 is a front view of the main part in the cull cutting of the hoop-shaped lead frame.
[0003]
In FIG. 10, 11 is a lead frame made of a strip-shaped metal material, etc., on which one or both forming elements 10 such as electronic components and semiconductors are placed at regular intervals by welding, bonding or caulking, Further, pilot holes 8a are also provided at regular intervals at both ends.
[0004]
Reference numeral 5 denotes a lower cavity block made of steel or the like, and a lower cavity 1, a gate 27, a gate 29 and a runner 28 are provided on the upper surface, and the lower cavity 1 includes the gates 29 and 27 and the gates 29 and 27. The other end is connected in communication with the runner 28 in the center. Further, a plurality of pilot pins 8b are provided outside the lower cavity 1 so as to protrude from the upper surface of the lower cavity block 5, and are inserted into the pilot holes 8a of the lead frame 11 so that the lead frame 11 is inserted into the lower cavity 1. Position at a predetermined location.
[0005]
Reference numeral 3 denotes an ejector pin made of steel or the like that can move up and down. The lower end is fixed to the upper surface of the ejector plate 6, the lower cavity block 5 is inserted, the tip protrudes from the bottom surface to the lower cavity 1, and the forming element 10 is heated. The molded body 20 completed by sealing with a curable resin is removed from the lower cavity 1 and taken out.
[0006]
Reference numeral 12 denotes an upper cavity block which can move up and down corresponding to the lower cavity block 5 made of steel or the like, and is an insertion hole through which the tip of the pilot pin 8b is inserted, and the forming element 10 is sealed with the resin facing the lower cavity 1. An upper cavity constituting the cavity is provided.
[0007]
Reference numeral 4 denotes a plunger made of steel or the like, which is movable up and down, and is slidably inserted into a lower pot 25 fixed and held on the lower cavity block 5 and is moved by a plunger drive mechanism (not shown). 4 is raised by a predetermined dimension to press a thermosetting resin, which is a molding resin for sealing molding, and send it to a cavity composed of a lower cavity 1 and an upper cavity in which a molded body 20 is formed, and a compression spring. The pressure is maintained as a predetermined resin pressure by the tension when 22 is compressed.
[0008]
In addition, 9 is a structural block which becomes a frame for constituting the lower mold part by the lower cavity block 5, the plunger plate 7, the plunger 4, and the like.
[0009]
FIG. 11A shows a state immediately after the tablet 2 made of a thermosetting resin, which is a molding resin, is supplied to the lower pot 25. From this state, the plunger 4 is raised by the plunger plate 7 and the plunger 4 is moved. When the tablet 2 is heated and compressed at the time of holding pressure, the compression spring 22 is compressed.
[0010]
In FIG. 13, reference numeral 43 denotes a molding upper die placed on the lower surface of the crown 43a, 44 denotes a molding lower die placed on the upper surface of the platen 44a immediately below the molding upper die 43, and positions adjacent to the respective molds. The same number of plungers 4 as the cals formed in the lower pot 25 in the molding lower mold 44 are arranged. Reference numeral 30 denotes a runner cutting lower mold for cutting the runner trace formed by the cal 21 and the runner 28 of the lead frame 11 into a predetermined shape. Reference numeral 30a denotes a runner cutting upper mold that faces the runner cutting lower mold 30 and is driven by an air cylinder 31a. , 32 is a driving roller for conveying the hoop-like lead frame 11, 31 is an air cylinder for moving the lead frame 11 up and down, and 33 is a chute for discharging the cut and separated culls and runners.
[0011]
Next, the sealing molding operation will be described. Powder or tablet-like thermosetting resin is supplied into the lower pot 25 by a supply mechanism (not shown), and the forming lower mold 44 is raised by a mold clamping mechanism (not shown), and the forming element 10 is placed. The pilot pin 8b is inserted into the pilot hole 8a of the lead frame 11 and positioned for clamping.
[0012]
Then, the thermosetting resin in the lower pot 25 is fed into the cavity formed by the upper cavity and the lower cavity 1 by the drive of the plunger 4, and the plunger 4 is stopped at the position where the filling in the cavity is completed. .
[0013]
On the other hand, during the mold clamping operation, the runner traces by the cull 21 and the runner 28 attached to the lead frame 11 that has been molded in the previous cycle are cut and removed. In other words, the runner cutting upper die 30a is moved downward by driving the air cylinder 31a, and the lead frame 11 is sandwiched and held between the runner cutting lower die 30 and then the punch and die (not shown) built therein. Cull 21 and runner traces are cut out and discharged through chute 33.
[0014]
After the predetermined time has elapsed and the thermosetting resin is cured, the lower mold 44 is lowered and stopped, and the lead frame 11 formed with the molded body 20, the cal 21, and the runner trace is attached to the ejector pin 3. Is separated from the lower cavity 1 by the upward drive. Thereafter, the lead frame 11 is raised by driving the air cylinder 31, and the lead frame 11 is transported by a predetermined amount by the rotational driving of the driving roller 32, and then the process proceeds to the next cycle.
[0015]
[Problems to be solved by the invention]
However, the conventional sealing molding apparatus has the following problems. The pressure holding operation after injection and filling of the thermosetting resin, which is a molding resin, is performed by causing the plunger 4 to generate a predetermined pressure with the tension of the compression spring 22, and changes in characteristics due to the initial deterioration peculiar to the compression spring 22. For example, a pressure change occurs due to deterioration due to the life of several million shots.
[0016]
Further, it is difficult to maintain a certain pressure against the variation in the weight of the thermosetting resin in powder or tablet form or the difference in volume of the forming element 10 placed on the lead frame 11.
[0017]
Furthermore, when the thermosetting resin is injected and filled, the resin that has reached a low viscosity enters the gap between the plunger 4 and the lower pot 25 and adheres in a solidified state. May occur, and pressure loss in the pressure holding process may cause unfilling of the cavity and generation of voids.
[0018]
In the above-mentioned continuous cycle operation, since the pressure loss corresponding to the sliding resistance of each plunger 4 cannot be measured individually, there is a problem in resin injection that it is impossible to suppress the occurrence of molding defects in the plunger with abnormal sliding. It was.
[0019]
Then, when molding a two-strip lead frame as shown in FIG. 12, when the volume of the molded body exceeds a predetermined amount, a difference occurs in the resin filling completion time in one row and the other row. In addition, there is a problem at the time of filling that the void generation rate of the molded body on the other row side becomes high.
[0020]
Further, in the cutting of the cull and runner traces in the arrangement as shown in FIG. 13, the dimension in the longitudinal direction of the runner cutting mold is determined by the number and arrangement of pots on the molding mold. It is necessary to install a mold with the same dimensions. The larger the number of pots, the larger the dimensions of the runner cutting mold, resulting in higher costs and the larger overall apparatus.
[0021]
In addition, it is necessary to prepare multiple tablets with different specifications when dealing with product types that require tablets with different weights, compared to the method of supplying tablet-shaped molding resin with a predetermined weight using a supply alignment mechanism such as a parts feeder. There was a management problem that there was.
[0022]
Furthermore, when the molding die is cleaned using a cleaning resin or a release resin, the tablet is manually supplied into the molding die using a tablet supply jig (not shown) to perform the molding operation. Start. At this time, there is a problem of safety due to manual work with respect to a plurality of cleaning moldings.
[0023]
Furthermore, when forming a hoop-shaped lead frame having a plurality of culls and runner traces, due to defective mold release after molding or cull or runner breakage during lead frame transport before next cycle molding, Due to the remaining of the above-mentioned kull and runner traces, there is a problem that the mold may be damaged at the time of mold clamping in the next molding.
[0024]
The present invention is intended to solve the above-described conventional problems, and there is little variation in holding pressure after filling with a molding resin. , It can be confirmed that it is molded at a predetermined pressure during continuous operation, The molding resin can be evenly injected into all the cavities for sealing the double-row lead frame, and runners and culls can be cut in a small space regardless of the number of pots in the mold. Can be switched easily, automatic supply and continuous molding of the cleaning resin tablet and mold conventional resin tablet in the device is possible, and the sealing molding device that can detect the remaining runner and cull and prevent the mold from being damaged The purpose is to provide.
[0025]
[Means for Solving the Problems]
In order to solve the above-described problems, the sealing molding apparatus of the present invention has the following configuration.
[0026]
According to a first aspect of the present invention, there is provided a molding die for transferring a strip or a hoop-like lead frame on which a forming element constituting a molded body is placed and sealing the resin to the forming element of the lead frame. And a plunger for injecting and filling powder or tablet-shaped molding resin into the cavity from the pot of the molding die, and actuating according to the movement of this plunger, and at the time of injection of molding resin, just before completion of filling or filling Later, it has a movable plunger that pressurizes and holds the molding resin at a predetermined pressure by hydraulic pressure at an arbitrary timing. A detection mechanism for detecting whether or not the operation of the movable plunger is affected by the sliding resistance after switching the pressure inside the hydraulic mechanism for driving the movable plunger to a low pressure at a predetermined timing; did This is a sealing molding device, and the resin pressure before and after the completion of filling can be switched arbitrarily, the bubbles that have entered inside in the molten state of the molded resin are discharged to the outside, and the bubbles are compressed It can be confirmed that it is molded at a predetermined pressure during continuous operation. It has the action.
[0027]
A second aspect of the present invention is a sealing molding apparatus according to the first aspect of the present invention, wherein a predetermined pressure is applied to the plunger using hydraulic pressure to inject or hold the molding resin, and the powder or Even with variations in the weight of the tablet-like thermosetting resin or the volume difference of the forming elements in the lead frame, it is possible to hold the molding resin at a constant pressure against each plunger at all times. It has the effect that a uniform pressure can be applied to the cavity.
[0028]
The invention according to claim 3 is the sealing molding apparatus according to claim 1 or 2, wherein the plunger and the movable plunger are formed as an ejection mechanism for releasing a cull formed by their operation. Thus, the plurality of ejector pins originally installed in the peripheral portion of the cal can be deleted, and the mold structure is simplified.
[0029]
According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the resin burrs adhering to the sliding surfaces of the movable plunger and the pot are removed by cleaning with a brush and suction. This sealing molding device is configured to have an effect of preventing an increase in sliding resistance and preventing pressure loss in a pressure holding step after injection of molding resin.
[0030]
Claim 5 The invention described in claim 1 4 In the invention described in any one of the above, in the resin-sealing molding of the forming element placed on the double strip-shaped strip or the hoop-shaped lead frame, the pot and the pot are arranged so that the resin flows evenly into all the cavities. This is a sealing molding apparatus in which runners are arranged in the vicinity of both side ends of the lead frame, and has an effect of preventing unfilling of the molding resin into the cavity and generation of voids.
[0031]
Claim 6 The invention described in claim 1 5 In the invention described in any one of the above, the lead frame is a sealing molding apparatus in which a cull removing mechanism including a roller that refracts and cuts the cull and a roller that supports and conveys the lead frame is installed during the conveyance of the lead frame. By removing the cull in synchronization with the transfer operation, the cycle time can be shortened, and it can be incorporated into the lead frame transfer mechanism regardless of the number of pots and the number of molds, thereby saving space. .
[0032]
Claim 7 The invention described in claim 1 6 In the invention described in any one of the above, in order to supply a tablet-shaped molding resin into a pot of a molding die, a sealing molding apparatus to which a tablet molding mechanism for molding a powder resin into a tablet is added, The thickness can be set thin or small, and the yield of sealing molding can be improved.
[0033]
Claim 8 The invention described in claim 1 7 In the invention described in any one of the above, in order to clean the molding die, a sealing molding apparatus to which a mechanism for continuously supplying the cleaning resin tablet and the release resin tablet into the molding die pot is added, There is no danger and trouble of manually supplying the tablet to the mold using a dedicated jig or the like, and it has the effect that it can be operated safely and easily as in the normal molding process.
[0034]
Claim 9 The invention described in claim 1 8 In forming the hoop-shaped lead frame having a plurality of culls in the invention described in any one of the above, Of Cal It is a sealing molding apparatus in which a presence / absence detection mechanism is added in a molding die, and has the effect of preventing the die from being broken by detecting the remaining of the cull on the molding die.
[0035]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
Hereinafter, the sealing molding apparatus in Embodiment 1 of this invention is demonstrated using drawing. 1 is a cutaway perspective view of a main part of a sealing molding apparatus according to Embodiment 1 of the present invention, FIGS. 2 (a) and 2 (b) are cross-sectional views of a main part showing resin sealing parts before and after the molding, and FIG. 3 is molding. FIG. 4 is a cross-sectional view showing the movable plunger at the normal position in the mold open state immediately after, FIG. 4 is a cross-sectional view showing the movable plunger at the abnormal position in the same state, and FIG. 5 detects the abnormality of the movable plunger due to the same state. FIG. 6 is a perspective view of a main part showing the cull removing mechanism, FIG. 7 is an enlarged side view showing a local configuration of the mechanism, and FIGS. 8A and 8B are local configurations of the mechanism. FIG.
[0036]
In addition, the same code | symbol is provided to the component and member same as the prior art, and detailed description is abbreviate | omitted.
[0037]
1, 2, and 3, a plurality of movable plungers 17 are arranged in the upper cavity block 12 so as to be vertically movable at equal intervals. The hydraulic isobaric pin 18 can generate a predetermined pressure by one path in the flow passage in the hydraulic block 19, and is always added in the direction in which the hydraulic isobaric pin 18 is lowered.
[0038]
In addition, the movable plunger 17 is disposed so as to face the position of the center portion of the runner 16 that connects the two lower pots 25 that are disposed corresponding to the two lower cavities 1. The central portion of the provided upper pot 26 is inserted and slidable. That is, a configuration in which the lower pot 25 and the upper pot 26 are arranged at equal and equal intervals in the vicinity of both end portions in the width direction of the lead frame 11 and the resin is uniformly injected into the upper pot 26 from both directions of the lower pot 25. It is.
[0039]
Reference numeral 7 denotes a plunger plate, which holds a plurality of plungers 4 that do not incorporate a spring mechanism, and is lifted by a plunger drive mechanism (not shown) that uses hydraulic pressure. By raising the plunger 4 by a predetermined dimension, the molding resin is injected and filled into the cavity portion formed by the upper cavity 14 and the lower cavity 1 to form the molded body 20. The upper cavity 14 is formed in the upper cavity block 12 so as to face the lower cavity 1 (see FIG. 2).
[0040]
15 is a cull formed by the upper pot 26 and the movable plunger 17, and the culls 21 on both sides thereof are formed by the lower pot 25 and the plunger 4, and these culls 15, 21 are formed by the runner 16. The formed body 20 and the cull 21 are connected by a runner trace formed by a runner 24 provided between the lower cavity 1 and the lower pot 25.
[0041]
Reference numerals 23a and 23b denote a plurality of sets of transmission-type sensors, in which the optical axes are aligned in the vicinity of the upper end portion of the hydraulic isobaric pin 18 at a regular position. Then, the movable plunger 17 at a position different in height from the other positions that are not regular positions puts the optical axis in a light-blocking state, and the abnormal state is detected.
[0042]
Next, the injection and filling operation of the molding resin in the sealing molding will be described with reference to FIGS. First, a strip or hoop-like lead frame 11 on which a forming element constituting the molded body is placed is transferred by a transfer mechanism (not shown) into a molding die for resin sealing molding. 2 (b), the tablet 2 is supplied to the lower pot 25 in the lower cavity block 5 and the mold is closed, and then the plunger 4 is moved upward by driving a plunger drive mechanism (not shown). As shown in FIG. 2A, the molten thermosetting resin, which is a molding resin, is injected and filled into the cavity portion constituted by the lower cavity 1 and the upper cavity 14 as shown in FIG.
[0043]
At this time, the pressure applied to the hydraulic isobaric pin 18 is the predetermined pressure described above from the start of resin injection, that is, the pressure A in FIG. 5, and the molding resin is injected and filled into the cavity. As the resin fills the upper pot 26, the movable plunger 17 is pressed upward and moved, so that the predetermined pressure is applied to the molding resin in the cavity portion. Become.
[0044]
At this time, even if there are variations in the plurality of tablets 2 or differences in the shape of the forming element 10, the thickness of the kull 15 having the l dimension in FIG. Will be held at a uniform pressure.
[0045]
That is, the holding pressure after the injection and filling of the molding resin is changed to the pressure B that is optimum for the holding pressure shown in FIG. 5. After the molding resin is injected into the cavity portion by the plunger 4 and filled, a plurality of pots 25 are added. , 26 are pressed by the pressure plunger B by the movable plunger 17 using hydraulic pressure in which the runners 16 are connected to each other, and a constant and uniform resin pressure is always applied to each cavity portion. The pressure A may be continued depending on the shape of the molded body 20, the forming element 10, or the number of sealing moldings performed at one time.
[0046]
Next, the mold release operation after completion of the pressure holding for a predetermined time will be described. First, the plunger 4 is moved slightly downward as shown in FIG. 5 so as to separate its tip from the molding resin. The movable plunger 17 performs a mold opening operation with the hydraulic pressure necessary for releasing the cull 15 from the upper pot 26, that is, the pressure A or the pressure B, and the operation and the movable plan based on the hydraulic pressure. By making the jar 17 move downward, the mold is released from the upper cavity 14 and the upper pot 26 (eject).
[0047]
On the other hand, in this mold opening operation, as shown in FIG. 5, the plunger 4 is raised further upward than the position at the time of resin sealing molding (pressure-holding state), so that the cal 21 formed by the lower pot 25 is obtained. Is released from the lower cavity block 5. At the same time, it goes without saying that the mold is released from the lower cavity 1 of the molded body 20 sealed with resin by raising the ejector pin 3 upward.
[0048]
If the molding resin enters the gap between the sliding portions of the movable plunger 17 and the upper pot 26 upon completion of the mold release of the molded body 20, as a result, the molded resin 20 is solidified on the sliding surface of the movable plunger 17. Resin burrs will adhere. In order to remove the resin burrs, when releasing the mold, as shown in FIG. 2B, the side surface of the tip of the movable plunger 17 that protrudes below the upper parting surface is brushed (see FIG. (Not shown) and a cleaning operation by vacuum suction are performed for each molding cycle, so that a stable sliding surface without resin burrs is always maintained.
[0049]
Next, it will be described that the plurality of movable plungers 17 manage a state where there is no pressure loss in the sliding resistance of the sliding portion caused by the resin burr, and that the holding pressure by the predetermined pressure is guaranteed. When the cull 15 is released from the upper pot 26, the hydraulic pressure for driving is changed from the strong pressure necessary for the cull 15 to be separated from the upper pot 26 to the pressure shown in FIG. C, for example 98 × 10 ^Four By switching to a low pressure of Pa or less, the movable plunger 17 is moved downward until the tip is at the moving end position of the holder 13 as shown in FIG.
[0050]
At this time, when at least one of the plurality of movable plungers 17 has a sliding resistance equal to or higher than the set pressure at the low pressure, the movable plunger 17 does not move to a predetermined moving end position as shown in FIG. Due to the displacement of the plunger 17, the pair of sensors 23 a and 23 b are shielded from light at the tip of the movable plunger 17 and detected as abnormal. Therefore, necessary operations such as an abnormality display and warning or an operation stop of the apparatus are performed based on the abnormality detection.
[0051]
Next, as a layout of the cull and runner in the sealing molding of the double strip-shaped strip or hoop-shaped lead frame according to the present invention, as shown in FIG. 1 and FIG. The cull 15 is formed in the upper pot 26 through which the movable plunger 17 is inserted, and is connected to each other by a runner trace by the runner 16. Further, the molten molding resin is evenly injected from the lower pot 25 through the runner 24 into the cavity portion constituted by the lower cavity 1 and the upper cavity 14 and filled.
[0052]
Next, the cull removing mechanism after sealing molding according to the present invention will be described with reference to FIGS. Reference numeral 35 denotes a cutting wheel mounted on both side surfaces of the pin roller 36, and is driven to rotate in synchronization with the hoop presser roller 34 by a timing pulley 39 and a timing belt 40 attached to the outer side surface of the pin roller 36. The pin roller 37 pitch-transfers the lead frame 11 for every one pitch of the sealing molding by the rotational drive of the servo motor 38. Reference numeral 41 denotes a chute for discharging the cut and separated culls, and reference numeral 42 denotes a cull abutment plate for preventing the culls from scattering and falling and guiding them to the chute 41.
[0053]
Next, the cull removing operation will be described with reference to FIG. The outer peripheral portion of the cutting wheel 35 is provided with a concavo-convex shape at regular intervals. A cull 15 having a projection on the concave portion is fitted, and a cull 21 having no projection is fitted on the convex portion. The lead frame 11 is aligned as described above, and the culls 15 and 21 are refracted while rotating downward in the direction of the arrow of the cutting wheel 35 at the concave and convex portions, cut and separated. At this time, the runner traces by the runners 16 and 24 connecting the cals 15 and 21 and the molded body 20 are located on the lower surface of the lead frame 11, and therefore the concave and convex shape of the cutting wheel 35 and the projection direction of the cals are matched. Thus, the stress on the lead frame 11 can be minimized. In addition, as shown in FIGS. 8A and 8B, the cull cutting operation uses the runner trace by the runner 24 and the contact point of the hoop press roller 34 as a fulcrum so that the molded body 20 itself is not stressed. Is refracted by the cutting wheel 35 to remove the cals 15 and 21 and sent to the chute 41 to be eliminated.
[0054]
That is, a cull removing mechanism including the cutting wheel 35, the pin roller 36, the hoop presser roller 34 and the like described above is installed immediately before the conveying roller of the lead frame 11 immediately after the sealing molding, and the lead frame of the lead frame is connected to the cull removing mechanism. By carrying the lead frame while winding and rotating the upper surface side, runner marks and culls are removed.
[0055]
Next, a method for detecting the occurrence of cull breakage during conveyance of a hoop-shaped lead frame having a plurality of culls will be described. In FIG. 1, reference numeral 60 denotes a reflection type sensor composed of a photoelectric switch, which is provided corresponding to the row position in the vicinity of both side ends of the lead frame 11 on which the cals 15 and 21 are formed. That is, the sensor 60 is installed in the direction in which the pots 25 and 26 provided in the molding die are aligned in the feed direction of the lead frame 11 and is located downstream in the transport direction of the lead frame 11. This sensor 60 detects the presence or absence of the culls 15 and 21 formed by a molding die depending on whether or not a predetermined number of culls have passed during conveyance of the lead frame 11. The position where the sensor 60 is set by the photoelectric switch may be a position where the culls 15 and 21 formed by resin sealing molding can be detected in the transport path of the lead frame 11, but in particular, the calf immediately after being formed by the molding die The detection is advantageous from the viewpoint of the safety of the apparatus.
[0056]
In this way, a sensor 60 for detecting defects in the molding die is installed against cull bending or dropping of the cull or the like on the molding die during lead frame conveyance, and conveyance is performed with the cull attached immediately after molding. In this case, the number of culls is counted, and when the number is less than the predetermined number, the apparatus is immediately stopped and a warning is displayed.
[0057]
(Embodiment 2)
Next, the sealing molding apparatus in Embodiment 2 of this invention is demonstrated using FIG. In FIG. 9, reference numeral 45 denotes a tablet molding mechanism, which is a configuration of a rotary press that feeds powder resin from a hopper, measures a predetermined weight of resin, and presses it. A tablet outlet is provided at one location of a rotating plate 59 provided in the tablet molding mechanism 45, and the continuously molded tablets 2 are transferred to the conveyor 47 and aligned in a row, and pass through a photoelectric switch 48 as a sensor. The tablet 2 is sent and supplied until the photoelectric switch 49 is shielded from light.
[0058]
Thereafter, the shutter 46 is opened, the conveyor 47 is operated, and the tablet 2 is transferred to the escape slider 52. The transfer dimension pitch of the tablet 2 in the escape slider 52 is equal to the pitch dimension between pots of the molding die 56 (same as described in the first embodiment) placed on the platen 57, and all the transfers of the tablet 2 are performed. When the replacement is completed, the escape slider 52 is moved to the tablet supply mechanism 54, and the escape slider 52 is on standby after the tablet 2 is transferred again.
[0059]
When the sealing molding is completed in the previous step (not shown) and the lead frame 11 for the next cycle is fed by the drive of the hoop feeding mechanism 58, the tablet supply mechanism 54 is advanced to advance the molding die 56. The tablet 2 is supplied to the lower pot 25. That is, for a variety of products having different tablet weights, a powder molding press is installed in the sealing molding apparatus, and the measurement setting of the powder resin is arbitrarily changed.
[0060]
Next, supply of the cleaning resin tablet and the release resin tablet will be described. The cleaning resin tablet and the release resin tablet are transferred from the two parts feeders 50 to the escape slider 52 horizontally moved by the direct robot 53 via the conveyor 51 in the same manner as the tablet 2 for molding. The supply mechanism 54 supplies the molding die 56 to a location (lower pot 25) corresponding to a predetermined location. That is, at the time of cleaning molding, the cleaning resin tablet and the release resin tablet are automatically supplied, and the number of operations can be arbitrarily set.
[0061]
In the second embodiment, the molding die is cleaned by using a hoop-shaped lead frame and sequentially transporting the molded product for cleaning using the lead frame. However, a strip-shaped lead frame is used. In this case, a cleaning molding formed by the molding die 56 using the cleaning mechanism 55 shown in FIG. 9 may be carried out to the outside other than the lead frame conveyance path.
[0062]
【The invention's effect】
As described above, according to the present invention, by using the plunger driven by hydraulic pressure, the weight difference of the tablet or the volume difference of the forming element placed on the lead frame in the pressure-holding step after the molding resin is injected. On the other hand, apply equal pressure to all cavities and easily measure the sliding resistance of all movable plungers. Confirm that it is molded at the specified pressure with It is possible to assure the quality of the molded body, and to flow into the cavity by injecting from both sides (both sides in the width direction of the lead frame) facing each other in the injection of molding resin in a double strip-shaped strip or hoop-shaped lead frame. Molding defects such as unfilled and voids can be suppressed.
[0063]
In addition, the plunger itself can be used as a cull eject mechanism, a cull removal mechanism can be installed in the lead frame transport mechanism, and a cull detection mechanism can be installed. Cost reduction and mold breakage countermeasures can be achieved.
[0064]
In addition, it is possible to install the tablet molding mechanism and the cleaning tablet supply mechanism in the sealing molding apparatus, and there is an effect that the product type switching and workability are improved.
[Brief description of the drawings]
FIG. 1 is a perspective cutaway view of a main part of a sealing molding apparatus according to Embodiment 1 of the present invention.
FIG. 2 (a) Main part sectional view showing a resin sealing part after the molding.
(B) Main part sectional view showing the resin sealing part before molding
FIG. 3 is a cross-sectional view showing a movable plunger at a normal position in a mold open state of the apparatus.
FIG. 4 is a cross-sectional view showing a movable plunger at an abnormal position in the mold open state of the apparatus.
FIG. 5 is a diagram of plunger hydraulic control operation by the same device.
FIG. 6 is a perspective view of a main part showing a cull removing mechanism in the apparatus.
FIG. 7 is an enlarged side view of the main part of the mechanism.
FIGS. 8A and 8B are enlarged sectional views of main parts of the mechanism.
FIG. 9 is a plan layout view showing a sealing molding apparatus according to Embodiment 2 of the present invention.
FIG. 10 is a perspective view showing a main part of a conventional sealing molding apparatus.
11A is a cross-sectional view showing the operation of the plunger before resin injection in the apparatus. FIG.
(B) Sectional view showing the operation of the plunger during ejection of the device
[Fig. 12] Arrangement of cals and runners on the same 2 lead frame
FIG. 13 is a front view showing a main part in the cull cutting of the apparatus.
[Explanation of symbols]
1 Lower cavity
2 tablets
3 Ejector pin
4 Plunger
5 Lower cavity block
6 Ejector plate
7 Plunger plate
8a Pilot hole
8b Pilot pin
9 building blocks
10 Forming elements
11 Lead frame
12 Upper cavity block
13 Holder
14 upper cavity
15 Cal
16 runners
17 Movable plunger
18 Hydraulic isobaric pin
19 Hydraulic block
20 Molded body
21 Cal
22 Compression spring
23a, 23b sensor
24 Runner
25 Lower pot
26 Top pot
27 Gate
28 Runner
29 Gate
30 Runner cutting lower mold
30a Runner cutting upper die
31, 31a Air cylinder
32 Drive roller
33 Shoot
34 Hoop presser roller
35 cutting wheel
36 pin rollers
37 Pin Roller
38 Servo motor
39 Timing pulley
40 Timing belt
41 Shoot
42 Cull Plate
43 Upper mold
43a Crown
44 Lower mold
44a platen
45 Tablet molding mechanism
46 Shutter
47,51 conveyor
48, 49 photoelectric switch
50 parts feeder
52 Escape slider
53 Direct Robot
54 Tablet supply mechanism
55 Cleaning mechanism
56 Mold
57 Platen
58 Hoop feed mechanism
59 Rotating plate
60 sensors

Claims (9)

A molding die including a cavity for transferring a strip or a hoop-shaped lead frame on which a forming element constituting a molded body is placed, and sealing the resin to the forming element of the lead frame, and a molding resin in a powder or tablet shape A plunger that fills the cavity by injecting into the cavity from the mold, and is actuated in response to the movement of the plunger. A movable plunger that pressurizes and holds the molding resin at a predetermined pressure is provided , and the pressure inside the hydraulic mechanism that drives the movable plunger is switched to a low pressure at a predetermined timing. The sealing molding apparatus which has a detection mechanism which detects whether it is influenced by .   The sealing molding apparatus according to claim 1, wherein a plunger corresponding to the movable plunger is configured to apply a predetermined pressure using hydraulic pressure so as to inject or hold a molding resin.   The sealing molding apparatus according to claim 1, wherein the plunger and the movable plunger are ejecting mechanisms for releasing a cull formed by their operations.   The sealing molding apparatus according to claim 1, wherein resin burrs adhering to the movable plunger and the sliding surface of the pot are removed by cleaning with a brush and suction. In resin-sealing molding of forming elements placed on double strips or hoop-shaped lead frames, pots and runners are placed near both ends of the lead frame so that the resin flows evenly into all cavities. The sealing molding apparatus as described in any one of Claims 1-4 . During conveyance of the lead frame that is discharged from the molding die, according to any one of claims 1 to 5 in which the roller and the cull removal mechanism supporting the lead frame consists of conveying rollers were installed to cut refracts Cal Seal molding device. The sealing molding apparatus according to any one of claims 1 to 6 , further comprising a tablet molding mechanism for molding a powder resin into a tablet in order to supply a tablet-shaped molding resin into a pot of a molding die. The sealing molding apparatus according to any one of claims 1 to 7 , further comprising a mechanism for continuously supplying a cleaning resin tablet and a release resin tablet into a pot of the molding die in order to clean the molding die. In hoop leadframe molding having a plurality of local, the detection mechanism of the presence or absence of Cal after molding, encapsulation molding apparatus according to any one of claims 1-8 appended to the molding die.

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